| /* | 
 |  * Copyright 2019-2021 The OpenSSL Project Authors. All Rights Reserved. | 
 |  * | 
 |  * Licensed under the Apache License 2.0 (the "License").  You may not use | 
 |  * this file except in compliance with the License.  You can obtain a copy | 
 |  * in the file LICENSE in the source distribution or at | 
 |  * https://www.openssl.org/source/license.html | 
 |  */ | 
 |  | 
 | /* | 
 |  * EC_METHOD low level APIs are deprecated for public use, but still ok for | 
 |  * internal use. | 
 |  */ | 
 | #include "internal/deprecated.h" | 
 |  | 
 | #include <stdlib.h> | 
 | #include <string.h> | 
 | #include <openssl/err.h> | 
 | #include <openssl/rand.h> | 
 | #include "ec_local.h" | 
 | #include "s390x_arch.h" | 
 |  | 
 | /* Size of parameter blocks */ | 
 | #define S390X_SIZE_PARAM                4096 | 
 |  | 
 | /* Size of fields in parameter blocks */ | 
 | #define S390X_SIZE_P256                 32 | 
 | #define S390X_SIZE_P384                 48 | 
 | #define S390X_SIZE_P521                 80 | 
 |  | 
 | /* Offsets of fields in PCC parameter blocks */ | 
 | #define S390X_OFF_RES_X(n)              (0 * n) | 
 | #define S390X_OFF_RES_Y(n)              (1 * n) | 
 | #define S390X_OFF_SRC_X(n)              (2 * n) | 
 | #define S390X_OFF_SRC_Y(n)              (3 * n) | 
 | #define S390X_OFF_SCALAR(n)             (4 * n) | 
 |  | 
 | /* Offsets of fields in KDSA parameter blocks */ | 
 | #define S390X_OFF_R(n)                  (0 * n) | 
 | #define S390X_OFF_S(n)                  (1 * n) | 
 | #define S390X_OFF_H(n)                  (2 * n) | 
 | #define S390X_OFF_K(n)                  (3 * n) | 
 | #define S390X_OFF_X(n)                  (3 * n) | 
 | #define S390X_OFF_RN(n)                 (4 * n) | 
 | #define S390X_OFF_Y(n)                  (4 * n) | 
 |  | 
 | static int ec_GFp_s390x_nistp_mul(const EC_GROUP *group, EC_POINT *r, | 
 |                                   const BIGNUM *scalar, | 
 |                                   size_t num, const EC_POINT *points[], | 
 |                                   const BIGNUM *scalars[], | 
 |                                   BN_CTX *ctx, unsigned int fc, int len) | 
 | { | 
 |     unsigned char param[S390X_SIZE_PARAM]; | 
 |     BIGNUM *x, *y; | 
 |     const EC_POINT *point_ptr = NULL; | 
 |     const BIGNUM *scalar_ptr = NULL; | 
 |     BN_CTX *new_ctx = NULL; | 
 |     int rc = -1; | 
 |  | 
 |     if (ctx == NULL) { | 
 |         ctx = new_ctx = BN_CTX_new_ex(group->libctx); | 
 |         if (ctx == NULL) | 
 |             return 0; | 
 |     } | 
 |  | 
 |     BN_CTX_start(ctx); | 
 |  | 
 |     x = BN_CTX_get(ctx); | 
 |     y = BN_CTX_get(ctx); | 
 |     if (x == NULL || y == NULL) { | 
 |         rc = 0; | 
 |         goto ret; | 
 |     } | 
 |  | 
 |     /* | 
 |      * Use PCC for EC keygen and ECDH key derivation: | 
 |      * scalar * generator and scalar * peer public key, | 
 |      * scalar in [0,order). | 
 |      */ | 
 |     if ((scalar != NULL && num == 0 && BN_is_negative(scalar) == 0) | 
 |         || (scalar == NULL && num == 1 && BN_is_negative(scalars[0]) == 0)) { | 
 |  | 
 |         if (num == 0) { | 
 |             point_ptr = EC_GROUP_get0_generator(group); | 
 |             scalar_ptr = scalar; | 
 |         } else { | 
 |             point_ptr = points[0]; | 
 |             scalar_ptr = scalars[0]; | 
 |         } | 
 |  | 
 |         if (EC_POINT_is_at_infinity(group, point_ptr) == 1 | 
 |             || BN_is_zero(scalar_ptr)) { | 
 |             rc = EC_POINT_set_to_infinity(group, r); | 
 |             goto ret; | 
 |         } | 
 |  | 
 |         memset(¶m, 0, sizeof(param)); | 
 |  | 
 |         if (group->meth->point_get_affine_coordinates(group, point_ptr, | 
 |                                                       x, y, ctx) != 1 | 
 |             || BN_bn2binpad(x, param + S390X_OFF_SRC_X(len), len) == -1 | 
 |             || BN_bn2binpad(y, param + S390X_OFF_SRC_Y(len), len) == -1 | 
 |             || BN_bn2binpad(scalar_ptr, | 
 |                             param + S390X_OFF_SCALAR(len), len) == -1 | 
 |             || s390x_pcc(fc, param) != 0 | 
 |             || BN_bin2bn(param + S390X_OFF_RES_X(len), len, x) == NULL | 
 |             || BN_bin2bn(param + S390X_OFF_RES_Y(len), len, y) == NULL | 
 |             || group->meth->point_set_affine_coordinates(group, r, | 
 |                                                          x, y, ctx) != 1) | 
 |             goto ret; | 
 |  | 
 |         rc = 1; | 
 |     } | 
 |  | 
 | ret: | 
 |     /* Otherwise use default. */ | 
 |     if (rc == -1) | 
 |         rc = ossl_ec_wNAF_mul(group, r, scalar, num, points, scalars, ctx); | 
 |     OPENSSL_cleanse(param, sizeof(param)); | 
 |     BN_CTX_end(ctx); | 
 |     BN_CTX_free(new_ctx); | 
 |     return rc; | 
 | } | 
 |  | 
 | static ECDSA_SIG *ecdsa_s390x_nistp_sign_sig(const unsigned char *dgst, | 
 |                                              int dgstlen, | 
 |                                              const BIGNUM *kinv, | 
 |                                              const BIGNUM *r, | 
 |                                              EC_KEY *eckey, | 
 |                                              unsigned int fc, int len) | 
 | { | 
 |     unsigned char param[S390X_SIZE_PARAM]; | 
 |     int ok = 0; | 
 |     BIGNUM *k; | 
 |     ECDSA_SIG *sig; | 
 |     const EC_GROUP *group; | 
 |     const BIGNUM *privkey; | 
 |     int off; | 
 |  | 
 |     group = EC_KEY_get0_group(eckey); | 
 |     privkey = EC_KEY_get0_private_key(eckey); | 
 |     if (group == NULL || privkey == NULL) { | 
 |         ERR_raise(ERR_LIB_EC, EC_R_MISSING_PARAMETERS); | 
 |         return NULL; | 
 |     } | 
 |  | 
 |     if (!EC_KEY_can_sign(eckey)) { | 
 |         ERR_raise(ERR_LIB_EC, EC_R_CURVE_DOES_NOT_SUPPORT_SIGNING); | 
 |         return NULL; | 
 |     } | 
 |  | 
 |     k = BN_secure_new(); | 
 |     sig = ECDSA_SIG_new(); | 
 |     if (k == NULL || sig == NULL) { | 
 |         ERR_raise(ERR_LIB_EC, ERR_R_MALLOC_FAILURE); | 
 |         goto ret; | 
 |     } | 
 |  | 
 |     sig->r = BN_new(); | 
 |     sig->s = BN_new(); | 
 |     if (sig->r == NULL || sig->s == NULL) { | 
 |         ERR_raise(ERR_LIB_EC, ERR_R_MALLOC_FAILURE); | 
 |         goto ret; | 
 |     } | 
 |  | 
 |     memset(param, 0, sizeof(param)); | 
 |     off = len - (dgstlen > len ? len : dgstlen); | 
 |     memcpy(param + S390X_OFF_H(len) + off, dgst, len - off); | 
 |  | 
 |     if (BN_bn2binpad(privkey, param + S390X_OFF_K(len), len) == -1) { | 
 |         ERR_raise(ERR_LIB_EC, ERR_R_BN_LIB); | 
 |         goto ret; | 
 |     } | 
 |  | 
 |     if (r == NULL || kinv == NULL) { | 
 |         if (len < 0) { | 
 |             ERR_raise(ERR_LIB_EC, EC_R_INVALID_LENGTH); | 
 |             goto ret; | 
 |         } | 
 |         /* | 
 |          * Generate random k and copy to param param block. RAND_priv_bytes_ex | 
 |          * is used instead of BN_priv_rand_range or BN_generate_dsa_nonce | 
 |          * because kdsa instruction constructs an in-range, invertible nonce | 
 |          * internally implementing counter-measures for RNG weakness. | 
 |          */ | 
 |          if (RAND_priv_bytes_ex(eckey->libctx, param + S390X_OFF_RN(len), | 
 |                                 (size_t)len, 0) != 1) { | 
 |              ERR_raise(ERR_LIB_EC, EC_R_RANDOM_NUMBER_GENERATION_FAILED); | 
 |              goto ret; | 
 |          } | 
 |     } else { | 
 |         /* Reconstruct k = (k^-1)^-1. */ | 
 |         if (ossl_ec_group_do_inverse_ord(group, k, kinv, NULL) == 0 | 
 |             || BN_bn2binpad(k, param + S390X_OFF_RN(len), len) == -1) { | 
 |             ERR_raise(ERR_LIB_EC, ERR_R_BN_LIB); | 
 |             goto ret; | 
 |         } | 
 |         /* Turns KDSA internal nonce-generation off. */ | 
 |         fc |= S390X_KDSA_D; | 
 |     } | 
 |  | 
 |     if (s390x_kdsa(fc, param, NULL, 0) != 0) { | 
 |         ERR_raise(ERR_LIB_EC, ERR_R_ECDSA_LIB); | 
 |         goto ret; | 
 |     } | 
 |  | 
 |     if (BN_bin2bn(param + S390X_OFF_R(len), len, sig->r) == NULL | 
 |         || BN_bin2bn(param + S390X_OFF_S(len), len, sig->s) == NULL) { | 
 |         ERR_raise(ERR_LIB_EC, ERR_R_BN_LIB); | 
 |         goto ret; | 
 |     } | 
 |  | 
 |     ok = 1; | 
 | ret: | 
 |     OPENSSL_cleanse(param, sizeof(param)); | 
 |     if (ok != 1) { | 
 |         ECDSA_SIG_free(sig); | 
 |         sig = NULL; | 
 |     } | 
 |     BN_clear_free(k); | 
 |     return sig; | 
 | } | 
 |  | 
 | static int ecdsa_s390x_nistp_verify_sig(const unsigned char *dgst, int dgstlen, | 
 |                                         const ECDSA_SIG *sig, EC_KEY *eckey, | 
 |                                         unsigned int fc, int len) | 
 | { | 
 |     unsigned char param[S390X_SIZE_PARAM]; | 
 |     int rc = -1; | 
 |     BN_CTX *ctx; | 
 |     BIGNUM *x, *y; | 
 |     const EC_GROUP *group; | 
 |     const EC_POINT *pubkey; | 
 |     int off; | 
 |  | 
 |     group = EC_KEY_get0_group(eckey); | 
 |     pubkey = EC_KEY_get0_public_key(eckey); | 
 |     if (eckey == NULL || group == NULL || pubkey == NULL || sig == NULL) { | 
 |         ERR_raise(ERR_LIB_EC, EC_R_MISSING_PARAMETERS); | 
 |         return -1; | 
 |     } | 
 |  | 
 |     if (!EC_KEY_can_sign(eckey)) { | 
 |         ERR_raise(ERR_LIB_EC, EC_R_CURVE_DOES_NOT_SUPPORT_SIGNING); | 
 |         return -1; | 
 |     } | 
 |  | 
 |     ctx = BN_CTX_new_ex(group->libctx); | 
 |     if (ctx == NULL) { | 
 |         ERR_raise(ERR_LIB_EC, ERR_R_MALLOC_FAILURE); | 
 |         return -1; | 
 |     } | 
 |  | 
 |     BN_CTX_start(ctx); | 
 |  | 
 |     x = BN_CTX_get(ctx); | 
 |     y = BN_CTX_get(ctx); | 
 |     if (x == NULL || y == NULL) { | 
 |         ERR_raise(ERR_LIB_EC, ERR_R_MALLOC_FAILURE); | 
 |         goto ret; | 
 |     } | 
 |  | 
 |     memset(param, 0, sizeof(param)); | 
 |     off = len - (dgstlen > len ? len : dgstlen); | 
 |     memcpy(param + S390X_OFF_H(len) + off, dgst, len - off); | 
 |  | 
 |     if (group->meth->point_get_affine_coordinates(group, pubkey, | 
 |                                                   x, y, ctx) != 1 | 
 |         || BN_bn2binpad(sig->r, param + S390X_OFF_R(len), len) == -1 | 
 |         || BN_bn2binpad(sig->s, param + S390X_OFF_S(len), len) == -1 | 
 |         || BN_bn2binpad(x, param + S390X_OFF_X(len), len) == -1 | 
 |         || BN_bn2binpad(y, param + S390X_OFF_Y(len), len) == -1) { | 
 |         ERR_raise(ERR_LIB_EC, ERR_R_BN_LIB); | 
 |         goto ret; | 
 |     } | 
 |  | 
 |     rc = s390x_kdsa(fc, param, NULL, 0) == 0 ? 1 : 0; | 
 | ret: | 
 |     BN_CTX_end(ctx); | 
 |     BN_CTX_free(ctx); | 
 |     return rc; | 
 | } | 
 |  | 
 | #define EC_GFP_S390X_NISTP_METHOD(bits)                                 \ | 
 |                                                                         \ | 
 | static int ec_GFp_s390x_nistp##bits##_mul(const EC_GROUP *group,        \ | 
 |                                           EC_POINT *r,                  \ | 
 |                                           const BIGNUM *scalar,         \ | 
 |                                           size_t num,                   \ | 
 |                                           const EC_POINT *points[],     \ | 
 |                                           const BIGNUM *scalars[],      \ | 
 |                                           BN_CTX *ctx)                  \ | 
 | {                                                                       \ | 
 |     return ec_GFp_s390x_nistp_mul(group, r, scalar, num, points,        \ | 
 |                                   scalars, ctx,                         \ | 
 |                                   S390X_SCALAR_MULTIPLY_P##bits,        \ | 
 |                                   S390X_SIZE_P##bits);                  \ | 
 | }                                                                       \ | 
 |                                                                         \ | 
 | static ECDSA_SIG *ecdsa_s390x_nistp##bits##_sign_sig(const unsigned     \ | 
 |                                                      char *dgst,        \ | 
 |                                                      int dgstlen,       \ | 
 |                                                      const BIGNUM *kinv,\ | 
 |                                                      const BIGNUM *r,   \ | 
 |                                                      EC_KEY *eckey)     \ | 
 | {                                                                       \ | 
 |     return ecdsa_s390x_nistp_sign_sig(dgst, dgstlen, kinv, r, eckey,    \ | 
 |                                       S390X_ECDSA_SIGN_P##bits,         \ | 
 |                                       S390X_SIZE_P##bits);              \ | 
 | }                                                                       \ | 
 |                                                                         \ | 
 | static int ecdsa_s390x_nistp##bits##_verify_sig(const                   \ | 
 |                                                 unsigned char *dgst,    \ | 
 |                                                 int dgstlen,            \ | 
 |                                                 const ECDSA_SIG *sig,   \ | 
 |                                                 EC_KEY *eckey)          \ | 
 | {                                                                       \ | 
 |     return ecdsa_s390x_nistp_verify_sig(dgst, dgstlen, sig, eckey,      \ | 
 |                                         S390X_ECDSA_VERIFY_P##bits,     \ | 
 |                                         S390X_SIZE_P##bits);            \ | 
 | }                                                                       \ | 
 |                                                                         \ | 
 | const EC_METHOD *EC_GFp_s390x_nistp##bits##_method(void)                \ | 
 | {                                                                       \ | 
 |     static const EC_METHOD EC_GFp_s390x_nistp##bits##_meth = {          \ | 
 |         EC_FLAGS_DEFAULT_OCT,                                           \ | 
 |         NID_X9_62_prime_field,                                          \ | 
 |         ossl_ec_GFp_simple_group_init,                                  \ | 
 |         ossl_ec_GFp_simple_group_finish,                                \ | 
 |         ossl_ec_GFp_simple_group_clear_finish,                          \ | 
 |         ossl_ec_GFp_simple_group_copy,                                  \ | 
 |         ossl_ec_GFp_simple_group_set_curve,                             \ | 
 |         ossl_ec_GFp_simple_group_get_curve,                             \ | 
 |         ossl_ec_GFp_simple_group_get_degree,                            \ | 
 |         ossl_ec_group_simple_order_bits,                                \ | 
 |         ossl_ec_GFp_simple_group_check_discriminant,                    \ | 
 |         ossl_ec_GFp_simple_point_init,                                  \ | 
 |         ossl_ec_GFp_simple_point_finish,                                \ | 
 |         ossl_ec_GFp_simple_point_clear_finish,                          \ | 
 |         ossl_ec_GFp_simple_point_copy,                                  \ | 
 |         ossl_ec_GFp_simple_point_set_to_infinity,                       \ | 
 |         ossl_ec_GFp_simple_point_set_affine_coordinates,                \ | 
 |         ossl_ec_GFp_simple_point_get_affine_coordinates,                \ | 
 |         NULL, /* point_set_compressed_coordinates */                    \ | 
 |         NULL, /* point2oct */                                           \ | 
 |         NULL, /* oct2point */                                           \ | 
 |         ossl_ec_GFp_simple_add,                                         \ | 
 |         ossl_ec_GFp_simple_dbl,                                         \ | 
 |         ossl_ec_GFp_simple_invert,                                      \ | 
 |         ossl_ec_GFp_simple_is_at_infinity,                              \ | 
 |         ossl_ec_GFp_simple_is_on_curve,                                 \ | 
 |         ossl_ec_GFp_simple_cmp,                                         \ | 
 |         ossl_ec_GFp_simple_make_affine,                                 \ | 
 |         ossl_ec_GFp_simple_points_make_affine,                          \ | 
 |         ec_GFp_s390x_nistp##bits##_mul,                                 \ | 
 |         NULL, /* precompute_mult */                                     \ | 
 |         NULL, /* have_precompute_mult */                                \ | 
 |         ossl_ec_GFp_simple_field_mul,                                   \ | 
 |         ossl_ec_GFp_simple_field_sqr,                                   \ | 
 |         NULL, /* field_div */                                           \ | 
 |         ossl_ec_GFp_simple_field_inv,                                   \ | 
 |         NULL, /* field_encode */                                        \ | 
 |         NULL, /* field_decode */                                        \ | 
 |         NULL, /* field_set_to_one */                                    \ | 
 |         ossl_ec_key_simple_priv2oct,                                    \ | 
 |         ossl_ec_key_simple_oct2priv,                                    \ | 
 |         NULL, /* set_private */                                         \ | 
 |         ossl_ec_key_simple_generate_key,                                \ | 
 |         ossl_ec_key_simple_check_key,                                   \ | 
 |         ossl_ec_key_simple_generate_public_key,                         \ | 
 |         NULL, /* keycopy */                                             \ | 
 |         NULL, /* keyfinish */                                           \ | 
 |         ossl_ecdh_simple_compute_key,                                   \ | 
 |         ossl_ecdsa_simple_sign_setup,                                   \ | 
 |         ecdsa_s390x_nistp##bits##_sign_sig,                             \ | 
 |         ecdsa_s390x_nistp##bits##_verify_sig,                           \ | 
 |         NULL, /* field_inverse_mod_ord */                               \ | 
 |         ossl_ec_GFp_simple_blind_coordinates,                           \ | 
 |         ossl_ec_GFp_simple_ladder_pre,                                  \ | 
 |         ossl_ec_GFp_simple_ladder_step,                                 \ | 
 |         ossl_ec_GFp_simple_ladder_post                                  \ | 
 |     };                                                                  \ | 
 |     static const EC_METHOD *ret;                                        \ | 
 |                                                                         \ | 
 |     if ((OPENSSL_s390xcap_P.pcc[1]                                      \ | 
 |          & S390X_CAPBIT(S390X_SCALAR_MULTIPLY_P##bits))                 \ | 
 |         && (OPENSSL_s390xcap_P.kdsa[0]                                  \ | 
 |             & S390X_CAPBIT(S390X_ECDSA_VERIFY_P##bits))                 \ | 
 |         && (OPENSSL_s390xcap_P.kdsa[0]                                  \ | 
 |             & S390X_CAPBIT(S390X_ECDSA_SIGN_P##bits)))                  \ | 
 |         ret = &EC_GFp_s390x_nistp##bits##_meth;                         \ | 
 |     else                                                                \ | 
 |         ret = EC_GFp_mont_method();                                     \ | 
 |                                                                         \ | 
 |     return ret;                                                         \ | 
 | } | 
 |  | 
 | EC_GFP_S390X_NISTP_METHOD(256) | 
 | EC_GFP_S390X_NISTP_METHOD(384) | 
 | EC_GFP_S390X_NISTP_METHOD(521) |